BITSAT2015MathematicsProbabilityActual
A bag contains 3 red and 3 white balls. Two balls are drawn one by one. The probability that they are of different colours is.
Options
- A3 / 10
- B2 / 5
- C3 / 5
- DNone of these
Correct answer
C. 3 / 5
Step-by-step solution
Let A event that drawn ball is red B event that drawn ball is white Then AB and BA are two disjoint cases of the given event. array l P(A B+B A)=P(A B)+P(B A) =P(A) P ( B A )+P(B) P ( A B ) array = 3 6 3 5 + 3 6 3 5 = 3 5